Posterior Cranial Vault Distractor Osteogenesis for the Treatment of Chiari Malformation Type 1: A Systematic Review of the Literature.

Background: Although posterior cranial vault distraction osteogenesis (PVDO) is utilized routinely now for the treatment of craniosynostosis, its use as a treatment option for Chiari type 1 malformation (CM1) is limited to case reports and small retrospective case series.

Methods: The authors conducted a systematic review of the published literature for PVDO as a treatment for CM1. The primary outcomes were reported complications, symptom improvement, and reoperation rates in patients that had PVDO surgery for CM1. The authors further investigated differences between patients with CM1 with an associated genetic syndrome and craniosynostosis.

Results: In total, 42 patients with an average age of 41.1 months were used in our analysis. A total of 38.1% of the patients had a diagnosed syndrome, 78.6% of patients had associated craniosynostosis, and 26/42 (61.9%) total patients-reported symptom improvement. Of 26 patients that reported symptom improvement, 20 (76.9%) had associated syndromes and 6 (23.1%) did not ( P =0.011). In addition, of these 26 symptom improved patients, 17 (65.4%) were associated with craniosynostosis while 9 (36.4%) did not have craniosynostosis ( P =0.008).

Conclusions: Posterior cranial vault distraction osteogenesis seems to be a promising new surgical intervention for treatment of CM1. Most patients saw symptom improvement after treatment (61.9%). There was a clinically and statistically significant difference in symptom improvement for patients with syndromic CM1 when compared with nonsyndromic CM1 patients.